How to Make It
Preheat the oven to 375°. In a large saucepan, heat 2 tablespoons of the olive oil. Add the garlic and shallots and cook over moderately high heat until softened but not browned, about 3 minutes. Add the tomatoes, tomato paste, thyme sprig, rosemary and a generous pinch each of salt and pepper. Cook over moderate heat, stirring occasionally, until thick, about 20 minutes. Discard the thyme.
Meanwhile, line a baking sheet with parchment paper. On a work surface, brush 1 phyllo sheet with some of the melted butter and top with a second phyllo sheet. Continue brushing and layering the phyllo to make a stack of 5 sheets. Using a 5 1/2-inch plate as a guide, cut out 6 stacked phyllo rounds. Transfer the rounds to the baking sheet and cover with a sheet of parchment paper. Bake the phyllo rounds for about 12 minutes, or until crisp and golden. Discard the top paper.
Using the same plate, cut out 12 parchment paper rounds and brush 6 of them with the softened butter. Arrange the shrimp on the buttered paper rounds, cut side up, in a radial pattern, overlapping them slightly. Cover with the remaining paper rounds and refrigerate until chilled, or for up to 3 hours.
Preheat the oven to 550°. Working quickly, spoon 1/4 cup of the sauce over each phyllo base. Remove the top paper from each shrimp round and invert it onto 1 of the phyllo bases. Remove the remaining paper rounds and sprinkle the shrimp with the saffron, thyme leaves, salt and pepper. Drizzle with the remaining 2 tablespoons of olive oil and bake for about 7 minutes, or until the shrimp are pink and cooked through. Garnish with the basil and serve immediately.